The aim of our study was to prove that there exists a strong effect on reactive oxygen species level in host-parasitic relationship. The clarification of the role of enzymes involved in the defense mechanism can significantly contribute to the breeding of plant varieties with a natural defense mechanism, thereby reducing the amount of chemicals used in food production.

In our study, the effect of bean rust was investigated. The main physiological parameters, such as the relative chlorophyll content of the host plant, the amount of photosynthetic pigments, and the activity of superoxide dismutase (SOD) and lipid peroxidation (LP) were measured. The experiment was conducted both in field conditions and in a humidity tent. In both cases, significant changes in the relative chlorophyll content, and in the amount of photosynthetic pigments was measured. At both sampling times, an increase was found in enzyme activity (both superoxide-dismutase and lipid peroxidation) due to bean rust infection. Notably, in several cases, the observed differences were significant.

The obtained results indicate that bean rust inoculation has a significant effect on the physiological characteristics, superoxide-dismutase activity and the rate of lipid-peroxidase of common bean.

Keywords: bean, bean rust, chlorophyll, lipid peroxidation, superoxide-dismutase